ELECTRIC ACTUATORS WITH FAIL SAFE UNIT For automatic opening or closing of a valve in the event of an emergency

Transcription

1 ELECTRIC ACTUATORS WITH FAIL SAFE UNIT For automatic opening or closing of a valve in the event of an emergency

2 In recent years, safety requirements in process plants have become increasingly demanding. Even in case of emergency, the system must be safe for persons and the environment. Actuators play a crucial role here, since it is their task to open or close a valve in case of emergency and to ensure that the plant remains in safe condition. With the FQM fail safe unit, AUMA offers innovative and safe actuator solutions for automatic operation of valves in case of emergencies making use of stored mechanical energy. The FQM fail safe unit meets the requirements of safety-related applications up to SIL 2/SIL 3 and is virtually maintenance-free. An explosion-proof version is also available. MECHANICAL SOLUTION FOR UTMOST SAFETY When relying on safe opening or closing of a valve, mechanical actuator solutions provide top safety. In case of need, the new FQM fail safe unit generates the required torque by means of a constant force spring purely on a mechanical basis. No electrical power is required for fail safe operation. CONSTANT TORQUE The constant force spring motor with patent pending provides a constant torque during fail safe operation and this across the complete travel. Thanks to the overriding gear arrangement, the constant force spring is disengaged during normal operation and does not need to be operated. As a consequence, actuator sizing can be relatively small. VARIABLE RUNNING SPEEDS The operating speed for the fail safe operation is adjustable. Furthermore, the actuator can operate the valve into the defined end position at reduced speed. This avoids pressure peaks within the pipeline and protects the valve. ELECTRIC PART-TURN ACTUATORS WITH FQM FAIL SAFE UNIT 2

3 EASY INTEGRATION Actuators with FQM fail safe unit are integrated into systems in the same way as standard AUMA actuators. The fail safe unit seamlessly adapts to the modular AUMA product design. It is combined with AUMA SQ part-turn actuators. Integration into the DCS is made as for the standard devices by means of AC integral actuator controls. Operating concept, interfaces and communication remain homogeneous across all valves installed within the plant. EASY RETROFITTING Thanks to their identical interfaces, the fail safe unit can be retrofitted within existing plants. For example, if the safety requirements for an application have intensified. VERSATILE IMPLEMENTATION AUMA actuators with FQM fail safe unit are particularly suited to automate butterfly valves as well as ball and plug valves at a swing angle of 90. They are the perfect choice if part-turn actuators require safe opening or closing in case of emergencies. Industrial applications Fail safe actuators are used in all markets and applications. In water reservoirs, they prevent drainage in case of burst pipes, for example. In cooling system, they prevent overheating of ovens for example in case of conventional cooling system failure. Steam generating boilers in power plants and fire protection measures in road and railway tunnels are further typical examples. Applications in the oil & gas industry The oil & gas industry imposes highest quality standards not least due to the superior danger of potential explosions. The explosionproof fail safe unit caters for the required safety level. Overfill protections in tank farms, drainage protection in tanks and pipelines or use in gas regulating and metering stations are merely a few of the versatile implementations in the oil & gas industry

4 FUNCTION FQM fail safe unit AUMA part-turn actuators with fail safe unit ensure that the valve is operated to a safe position in the event of power failure or in case an emergency signal is issued. Selection can be made whether the valve is to be operated into position OPEN or CLOSED. Standard operation All AUMA actuator functions are available as usual in standard operation. The torque is transmitted directly from the actuator through the fail safe unit to the valve. Fail safe operation The fail safe operation is completely independent of the power supply and is exclusively supplied on a mechanical basis by means of the energy stored in the coiled up constant force spring. A fail safe operation is initiated in case of power failure or if an emergency signal is issued. This is independent of AC actuator controls. The constant force spring is activated during fail safe operation and transmits the generated torque to the valve by means of a planetary gearing. During the complete fail safe operation, the spring provides a virtually constant torque. FQM 1 1 Constant force spring motor The core of the fail safe unit is a mechanical constant force spring motor providing the required torque to open or close the valve in case of an emergency. When connecting the actuator to the mains and after release by the DCS, the fail safe unit is initialised and the constant force spring is fully wound by means of an electric motor. For this, the spring is wound in opposite direction on a drum. During the fail safe operation, the integrated electric motor additional acts as brake and slows down the spring allowing setting of various running speeds during fail safe operation. 4 2 Solenoid with toggle lever By means of a toggle lever, the solenoid retains the spring in the fully wound position. In case of power failure or if an emergency signal is issued, the solenoid releases the spring and initiates the fail safe operation. 4

5 AC Electric part-turn actuator The FQM fail safe unit is used in combination with AUMA SQ part-turn actuators. The electric actuator can thus be individually and perfectly adjusted to the application requirements: The combinations with the following versions are possible: SQ > > SQ part-turn actuators for open-close duty > > SQR part-turn actuators for modulating duty > > SQEx and SQREx part-turn actuators for potentially explosive atmospheres AC integral actuators controls AC integral actuator controls assume communication control between DCS and actuator. Actuator controls are available with various interfaces to the DCS allowing both parallel signal transmission and fieldbus communication. Supported are, for example, Profibus DP, Modbus RTU, DeviceNet and Foundation Fieldbus as well as HART and WirelessHART. Advanced diagnostic functions enable preventive maintenance and integration of actuators into asset management systems. Integral local controls also allow for local actuator operation. 2 3 Planetary gearing The planetary gearing acts as overriding gear arrangement. In standard operation it transmits the drive shaft movement directly to the part-turn movement of the valve. During standard operation, the constant force spring is disengaged and is not operated by the actuator. 3 During the fail safe operation, the planetary gearing transmits the energy stored in the spring to the valve. Here, the actuator is inactive. 4 End stops with integral end position switches The internal end stops limit the swing angle of the valve. The end position switches are automatically set during the setting procedure of end positions OPEN and CLOSED and do not require separate adjustment. 5 Valve attachment The interface to the valve is made in compliance with EN ISO The torque is transmitted from the output drive shaft to the valve by means of a splined coupling which is available in different versions: unbored, with square bore, two-flat or as bore with keyway. 5

6 Advantages of the AUMA scheme The main drawbacks of conventional solutions using simple return springs are that the spring transmits the highest torque at the start of the travel. Towards the end of the travel, the applied torque is reduced when it is needed most to ensure safe valve seating. Hence, the springs have to be oversized to ensure that the required torque is still supplied towards the end of the travel. With the constant force spring with patent pending by AUMA, the wrapped constant force spring drum supplies a virtually constant torque across full travel. Consequently, constant force spring motor sizing is lower than for conventional springs. Further advantage: Thanks to the overriding gear arrangement, the spring must not be operated during standard operation and remains completely wound. This allows selection of smaller actuators. Furthermore, premature spring fatigue can be prevented and the valve is protected against excessive torques. T Torque OPENLorem ipsum OPEN (0 ) CLOSED (90 ) Time Conventional return spring Required valve torque AUMA constant force spring

7 SERVICE CONDITIONS AUMA actuators with FQM fail safe unit are designed to highest reliability and long product life and fulfil their automation tasks in most severe and harsh environments. ENCLOSURE PROTECTION IP68 Like the actuators, the FQM fail safe unit is available with increased enclosure protection IP68 in compliance with IEC The permissible immersion height of 8 m head of water is specified for a max. duration of 96 hours. AMBIENT CONDITIONS The standard version of the FQM fail safe unit is suitable for temperatures of 30 C to +70 C. Further temperature ranges are available on request. CORROSION PROTECTION The AUMA corrosion protection system with the two-layer powder coating is certified by the TÜV and provides top-quality mechanical and chemical resistance. Actuators equipped with FQM fail safe units are suitable for environmental conditions C5-I and C5-M in compliance with EN ISO They comply the requirements for use in areas with high salinity, almost permanent condensation, and high pollution. EXPLOSION PROTECTION Both actuators and FQM fail safe units were tested and certified in close collaboration with national and international certification bodies. Approvals have been obtained from authorities worldwide for use in potentially explosive atmospheres, including ATEX (Europe), IECEx (international), FM (USA) and ROSTECHNADSOR/ EAC (TR-CU) (Russia). > > Explosion protection according to ATEX ATEX II2G Ex c IIB T3 or T4 > > Explosion protection according to FM: Class I, Div. 1, Groups C,D Class II, Div. 1, Groups E,F,G Class III FIREPROOF VERSION AUMA actuators with FQM fail safe units are available in fireproof version to ensure safe closing and opening of valves even in the event of a fire. Devices fitted with K-MASS TM fire protection coating preserve functionality during 30 minutes at temperatures as high as 1,100 C. Consequently, they fulfil the requirements in compliance with UL SIL Fail safe requirements and functional safety are often closely linked. In particular, components with increased reliability and lower probability of failure are required if system requirements include safeguarding the safety for persons and environment in case of emergencies. The AUMA fail safe unit fulfils highest requirements in terms of functional safety according to IEC Further information can be provided on request. TECHNICAL DATA Type FQM 05.1 FQMEx 05.1 FQM 07.1 FQMEx 07.1 FQM 10.1 FQMEx 10.1 FQM 12.1 FQMEx 12.1 Mains voltage Control voltage ESD input Operating time fail safe operation Torque Swing angle Suitable part-turn actuator Valve attachment [s] [Nm] EN ISO to SQ 05.2 F07 F10 F07 8 to Adjustable SQ 07.2 F10 between 80 and 15 to F10 SQ 10.2 F12 13 to 39 1,200 SQ 12.2 F12 F14 3-phase AC current: 380 V 690 V, 50 Hz/60 Hz 1-phase AC current: 100 V 240 V, 50 Hz/60 Hz 24 V DC 7

8 AUMA Riester GmbH & Co. KG Aumastr Muellheim Germany Tel Fax info@auma.com AUMA subsidiaries and representatives are implanted in more than 70 countries. For detailed contact information, please refer to our website. Subject to changes without notice. The product features and technical data provided do not express or imply any warranty. Y /003/en/1.18 Certificate Registration No /